Composite *Protoavis*?

["Jaime A. Headden" <qilongia@yahoo.com>]

Okay, Fellows, my opinion on this mess ... after a two year hiatus:

  There is some odd stuff in the *Protoavis* material that makes me question 
the unity of the form
of the animal, but I caution, this is from photos and illustrations, as I have 
yet to have high
quality photos from Sankar. Other than that, I can make some basic observations.

  Some of what Chatterjee labels as dorsals are in fact cervicals. An example 
is figure 4.3(p) in
Chatterjee's book. These are cervicals of a small theropod dinosaur, similar to 
ceratosaurian
cervicals, and it is likely they belong to a coelophysid of some sort.

  This has been my impression of the brain-case as well, numerously 
foraminated, and appearing to
be a juvenile of some sorts. Most sutures are well exposed. The frontals and 
parietals resemble
those of *Megalancosaurus* sensu Renesto, 1999, with long lateral wings on the 
frontals, forming a
T-shape.

  Cervicals of the paradigm, as has been noticed before (Renesto, 1999) appear 
to be
drepanosaurid, and this may be true of all identified cervicals. The sacrals 
and posterior dorsals
that Chatterjee identifies are also nearly identical to those of 
*Megalancosaurus* (figs. 4.3
[u-v], 4.5 [c]) (pers. obs.), whereas other dorsals and "caudals" appear to 
belong to a
coelophysid paradigm (fig. 4.3 [q-t]).

  The "manus" is so unwholly avian it's not funny: the carpus is apparently 
non-archosaurian, and
may or may not be a pes; I believe Sereno's impression comes from the long 
bones of the "foot",
but it bears no resemblance to a manus with which I am familar with throughout 
Reptilia.

  The femur, tibia, and astragalocalcaneum are classically ceratosaurian, and 
probably pertain to
a coelophysid along with the braincase and anterior "dorsals" (=cervicals). The 
femur has a
characteristically flattened head, rectangular in anterior view, and oriented 
anteromedially. The
slenderness of the femur and tibia seem to suggest immature qualities. The 
astragalocalcaneum is
classic ceratosaurian, perhaps more so than any other element, suggests that 
Chatterjee's paradigm
is not autochthonic.


=====
Jaime A. Headden

  Aaaaaaaaaaaaaaaaaaaahhhhhhhhhhhhhhhhhhr-gen-ti-na
  Where the Wind Comes Sweeping Down the Pampas!!!!

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